5 research outputs found
Spectral characterization of mangrove leaves in the Brazilian Amazonian Coast: Turiaçu Bay, Maranhão State
Mangrove vegetation in Amazonia: a review of studies from the coast of Pará and Maranhão States, north Brazil
Shrimp Farming as a Coastal Zone Challenge in Sergipe State, Brazil: Balancing Goals of Conservation and Social Justice
Interrelationships among ecological factors of brachyuran crabs, trees and soil in mangrove community assemblage in Northeast Brazil
Bioecology of the uçá-crab, Ucides cordatus (Linnaeus, 1763), in Vitória Bay, Espírito Santo State, Brazil
The biology of the Ucides cordatus in Vitória Bay (ES) was evaluated as a possible tool for population management. Sampling occurred monthly for about a year (October 1998 to September 1999) with biometric analysis (CW = carapace width; WW = total wet weight) and abiotic factors on four transects, each with four bands (margin to supratidal region). The density was 3.7±1.5 crabs.m-2 , with an increase toward the supratidal region, and depth of the galleries with 1.1 ± 0.3 m. The salinity of interstitial water differed between bands, being higher in the supratidal. There was significant correlation between the abundance of individuals and some environmental factors, the same occurring with open and closed burrows. The sex ratio showed a predominance of females (1.0M:1.6F), particularly between 50 and 75 mm (CW). The higher incidence of closed burrows occurred in August and September, while ovigerous females were recorded from January to April. The relationship WW/CW showed isometry for males (WW=0,425.10-3 LC3,0014; R²=0.99) and females (WW=0,439.10-3 LC2,97; R²=0.99). For the total population the average size (CW) and weight (WW) were 54.6±11.8 mm and 77.5±42.4 g, respectively. The population is under super-exploitation, requiring proper management for the viability of activity in the area.<br>A biologia de Ucides cordatus na Baía de Vitória (ES) foi avaliada como subsídio ao manejo populacional. As amostragens ocorreram mensalmente durante um ano (outubro/1998 a setembro/1999), com análise biométrica (LC = largura da carapaça; PE = peso total úmido) e de fatores abióticos em quatro transectos, com quatro faixas cada (margem à região supratidal). A densidade foi de 3,7±1,5 caranguejos.m-2, com incremento em direção à região supratidal, sendo a profundidade das galerias de 1,1±0,3 m. A salinidade da água intersticial diferiu entre as faixas, sendo mais elevada na região supratidal. Houve correlação significativa entre a abundância de exemplares e alguns fatores ambientais, o mesmo ocorrendo quanto as tocas abertas e fechadas. A razão sexual evidenciou um predomínio de fêmeas (1,0M:1,6F), particularmente entre 50 e 75 mm LC. A maior incidência de tocas fechadas ocorreu em agosto e setembro, enquanto as fêmeas ovígeras foram registradas de janeiro a abril. A relação PE/LC mostrou isometria para os machos (PE=0,425.10-3 LC3,0014; R²=0,99) e fêmeas (P=0,439.10-3 LC2,97; R²=0,99). Para o total da população a média de tamanho (LC) e peso (PE) foi de 54,6±11,8 mm e de 77,5±42,4 g, respectivamente. Os dados evidenciam que a população encontra-se sobrexplotada, requerendo manejo adequado para a viabilidade da atividade extrativa na área estudada